Lighting device, display device and television receiving device

Abstract

A backlight device 24 includes: a light-guide plate 20 that has a rectangular plate-like shape, of which one long-side end face is a main light-entering face 20 A and both short-side end faces are auxiliary light-entering faces 20 B; a plurality of main LEDs 28 A that are disposed in a line along the main light-entering face 20 A, and that emit light that is subsequently received by the main light-entering face 20 A; and a plurality of auxiliary LEDs 28 B that are disposed in a line along each auxiliary light-entering face 20 B, and that emit light that is subsequently received by the auxiliary light-entering faces 20 B. The auxiliary LEDs 28 B are configured such that a ratio of an area of light-emitting surfaces of the auxiliary LEDs 28 B to an area of the auxiliary light-entering faces 20 B is less than a ratio of an area of light-emitting surfaces of the main LEDs 28 A to an area of the main light-entering face 20 A.

1 : An illumination device, comprising:
 a light guide plate that has a rectangular plate-like shape, at least one long-side end face thereof being a main light-entering face and at least one short-side end face thereof being an auxiliary light-entering face;   a plurality of main light sources disposed in a line along the main light-entering face, such that light emitted by said main light sources enters said main light-entering face; and   a plurality of auxiliary light sources disposed in a line along the auxiliary light-entering face, such that light emitted by said auxiliary light sources enters said auxiliary light-entering face,   wherein a ratio of a total area of light-emitting surfaces of the auxiliary light sources to an area of the auxiliary light-entering face is less than a ratio of a total area of light-emitting surfaces of the main light sources to an area of the main light-entering face.   
     
     
         2 : The illumination device according to  claim 1 ,
 wherein the main light sources are disposed such that the light-emitting surfaces thereof face the main light-entering face,   wherein the auxiliary light sources are disposed such that the light-emitting surfaces thereof face the auxiliary light-entering face, and   wherein the ratio of the total area of the light-emitting surfaces of the main light sources to the area of the main light-entering face is represented by the formula B 1 ×N 1 ÷A 1 , and the ratio of the total area of the light-emitting surfaces of the auxiliary light sources to the area of the auxiliary light-entering face is represented by the formula B 2 ×N 2 ÷A 2 , where A 1  and A 2  represent the area of the main light-entering face and the area of the auxiliary light-entering face, respectively, B 1  and B 2  represent an area of the light-emitting surface of each of the main light sources and an area of the light-emitting surface of each of the auxiliary light sources, respectively, and N 1  and N 2  represent a number of the main light sources and a number of the auxiliary light sources, respectively.   
     
     
         3 : The illumination device according to  claim 1 ,
 wherein the main light sources that are disposed adjacent to each other have a substantially equal gap therebetween,   wherein the auxiliary light sources that are disposed adjacent to each other have a substantially equal gap therebetween, and   wherein the main light sources are disposed with a narrower gap therebetween than the auxiliary light sources.   
     
     
         4 : The illumination device according to  claim 1 , wherein both short-side end faces of the light guide plate are respectively the auxiliary light-entering face. 
     
     
         5 : The illumination device according to  claim 1 ,
 wherein only one of the long-side end faces of the light guide plate is the main light-entering face, and   wherein a distribution of the auxiliary light sources is closer to another of the long-side end faces of the light guide plate relative to said only one of the long-side end faces.   
     
     
         6 : The illumination device according to  claim 1 , wherein both long-side end faces of the light guide plate are respectively the main light-entering face. 
     
     
         7 : The illumination device according to  claim 1 , wherein the main light sources are disposed so as to face almost the entire main light-entering face. 
     
     
         8 : A display device, comprising:
 the illumination device according to  claim 1 ; and   a display panel that utilizes light from the illumination device to perform display.   
     
     
         9 : The display device according to  claim 8 , wherein the display panel is a liquid crystal panel that utilizes liquid crystal. 
     
     
         10 : A television receiver, comprising:
 the display device according to  claim 8 .